Electric self-playing piano attachment.



No 730,098. PATENTED JUNE 2, 1903.

G. H. DAVIS.

ELECTRIC SELF PLAYING PIANO ATTACHMENT. APPLICATION rum) 1020.23, 1898.-

10 110mm. 2 sums-sum amnm winmm amlgefiaauals W, 5y I r W no! Tm; mum:miss 00.. mow-Una. wmmmon. n. c.

No. 730,098. PATENTED JUNE 2, 1903.

v G. H. DAVIS.

ELECTRIC SELF PLAYING PIANO ATTACHMENT.

APPLICATION FILED DEC. 23. 1898.

2 SHEETS-SHEET 2.

10 MODEL.

ziiiiL-L THTT jzzaeiaz oz' g'ffflavsy UNITED STATE Patented June 2,1903.

PATENT OFFICE.

GEORGE IIOW'LETT DAVIS, OF NEWV YORK, N. Y.

SPECIFICATION forming part of Letters Patent No. 730,098, dated June 2,1903.

Application filed December 23,1898. Serial No. 700,159. (No model.)

To [bl Z whom, it may concern.-

Be it known that I, GEORGE HOWLETT DAVIS, a citizen of the UnitedStates, residing at New York, in the county of New York and State of NewYork, have invented a certain new, useful, and valuable Improvement inElectric Self-Playing Piano Attachments,-

of which the followingis a full, clear, and exact description.

My presentinvention relates to certain new and useful improvements inelectrical selfplaying pianos; and it is the prime object of theinvention to greatly simplify the general construction of instruments ofthis character and reduce the number of operating parts, so that thecost of manufacture and liability get out of order will also be reduced.

It is the purpose of this invention to operate the keys or thesound-producing devices of a musical instrument through the medium of aplurality of solenoid-magnets having direct connection with said keys orsound-producing devices, so as to obviate the employment of a rotarydrum, electromagnets, and friction-shoes, all of which have heretoforebeen largely usedin self-playinginstruments.

In order to enable others skilled in the art to understand, make, anduse my said improvements, I'will proceed to describe the same in detailand then follow said description with a series of claims definitelypointing out what I consider to be new and what I desire to cover bythese Letters Patent.

In the accompanying drawings, forming part of this specification, Figure1 is a transverse sectional view of a piano-keyboard with my improvementapplied to the under side thereof. Fig. 2 is an enlarged detailsectionalview of my solenoid-magnet, which forms the leading feature of thisinvention, together with the preferred form of striker-rod. Fig. 3 is amodified arrangement of my invention, showing the operating mechanismacting directly upon the sound-producing devices. Fig. 4 is a rear viewshowing"- the manner in which the solenoids are arranged and mounted. I

Enteringi'nto a detailed description of the several parts and theirmodus opercmcli, like numerals hereinafter employed refer to like partsin the several views of the drawings.

The piano-key 1 and the supporting-keyboard or frame2 are of the usualconstruction. The music-sheet holder, composed of the base 3, swingingframe 4, take-up roller 5, delivery-roller 6, contact-roller 7,contact-finger 8, and the perforated musicsheet 9, which latter servesto make and break the electric circuits between the said contact-rollerand contact-fingers, are all of the form shown in my Patent No. 546,582,dated September17, 1895; but it must be understood that mysolenoid-magnets, to be hereinafter more fully described, may be used inconnection with or be controlled by any operative form of circuit makingand breaking device.

In this instance I suspend my new action from a base-block 10, securedto the under side of the keyboard 2. The brackets 11, secured rigidly tothe base-block 10, secure and hold in rigid position the cross-beam 12.In said cross-beam are bored a series of round holes, and into each ofthese holes is inserted a helix of wire 13; having the terminals 14 and15, leading to the contact device. Within said helix is movablysupported an iron core 16, which is rigidly connected to the woodconnector 17 by means of the brass rod 18 sliding through the feltbushing 19 in the cap 20. The core 16 also bears at its lower end in thehushed hole 21 of cap 22. Interposed between the bottom of the connectorappurtenant parts, may be said to form anextension of the core 16,'saidparts all moving in unison therewith. Now Whenever the circuit iscompleted through the helix 13, forming with the core 16 a solenoidmagnet, then the core rises under the known laws applicable to thisspecial form of magnet, and the connector 17 and striker-rod 23 alsorise therewith and cause the top end of the latter or button 25 toimpinge the key 1, which in turn also rises and causes the superinducedpiano-action (not shown) to be thrown into action, causing the hammer tostrike the strings with a force depending upon the strength of thecurrent allowed to pass through the helix.

As above described, the helix of the solenoid is seated in a pocketformed in the crossbeam 12 in vertical alinement with the part of thekey of the sound-producing devices against which the rod 23 operates.There is an especial reason for this form of seating in that the partsare held accurately positioned in relation toeach other. Owing to thefact that the core of the solenoid moves vertically and is adjustablyconnected with the connector 17 should no support be provided whichwould hold the opposite ends of the helix against lateral movement therewould be a tendency for the upper end of the helix to become displacedfrom its position laterally. This is due to the fact that the upwardmovement of the core is positive and to a fixed position, and hence anyinaccuracy of adjustment or other cause might tend to attempt to limitthis upward movement, with the result that some portion of,tbe actuatingmechanism would necessarily give, probably in connection with theconnector or the rod 18,which would then tend to force the core to afalse direction of movement. This in turn would cause the upper end ofthe helix to be moved laterally and out of its proper position tooperate smoothly with the core. Any such tendencyis prevented by holdingthe opposite ends of the helix against displacement, whether by the useof a pocket which wholly incloses the vertical length of the helix orwhich simply incloses the opposite ends, and the use of a continuoussupport in this connection adds to the value, for the reason that suchdisplacement is prevented in each solenoid relatively to each other,such as might occur in the use of separate pockets secured to a base, asin the latter case the point of weakness would be in the securing meansbetween the pocket-support and its base.

As shown and described, the core 16 is adjustably secured to theconnector, and the latter is adjustably secured to the rod 23. Thisconstruction is of positive advantage in an operating device of thischaracter. As before stated, the core moves from an adjusted position toone which is fixed regardless of its length of movement, this movementbeing due to the current passing through the helix. The return movementof the core and the parts carried by it is due solely to the weight ofthe core, the cap 20 forming the stop against downward movement. Theupward movement of the core being due solely to the energizing of thehelix will depend for its rapidity of movement on the strength of thecurrent passing through the helix, a strong current causing a more rapidmovement than a Weak current, and on the distance which the coretravels. Instead of attempting to control this rapidity by varying thestrength of the battery used I adjust the position of the corerelatively to the helix so that a greater or less movement of the corein the helix, according to the distance between the top of the core andthe upper end of the helix, will control the rapidity of movement of thecore in the direction to sound the device. The adjustment thereforeserves to vary the rapidity of movement. This control of the rapidityserves two purposes first, to change the action of a piano,and,second,to govern the stroke of the hammer, the latter being hard'eras the core moves with greater rapidity. The controlling of the actionis important, inasmuch as different makes of pianos and oftentimesdifferent pianos of the same make have their actions operate to requirea touch which may vary from a weak to a strong touch, and there is alsoa variation in the length of the rocking movement of the keys. Where thetouch is weak, there is less requirement of rapid movement of the corethan where a strong touch is required, so that this adjustment forms aparticular part in controlling the movement of the action, and where theupward action is more rapid there is a quicker response to the action ofthe make-and-break device, enabling of the playing of music whererapidity is an especial feature, thus making a construction which ismore or less sensitive as the uses to which it is put require. Thereturn movement of the core is not due to the movement of the key, butto the weight of the core, together with the parts carried thereby, thusforming a positive-acting device which will instantly return the core toits initial position as soon as the circuit is broken.

It is understood, of course, that when the distance between the top ofthe core and the cap 20 is changed the rod 23 must also be adjusted sothat the key 2 will have no greater movement. In such case, especiallywhere the movement of the core is considerable, the button 25 willnormally be out of contact with the bottom of the key.

The principal advantage of this construction is its extreme simplicity,rendering it economical to manufacture, and having only one movable partit is unlikely to ever get out of order.

Instead of attacking the key of a piano it is obvious that myimprovement may be arranged to attack the sound-producing devices 26direct, as shown in Fig. 3.

What I claim is 1. In an electrical self-playing musical instrument thecombination with the soundactuating devices; of a plurality ofsolenoids, a cross-beam provided with means for supporting and embracingthe coils of said solenoids throughout their length, a weighted ironcore movable in each solenoid, the action of the solenoid moving saidcore in opposition to the weight of the core, means attached to eachcore for operating the sound-actuating devices, said means supportingthe core, and

IIC

contact making and breaking devices in circuit with the solenoids.

2. In an electric self-playing piano, the combination with the keysthereof, of a crossbeam mounted below said keys and provided with aplurality of pockets, a solenoid supported in each pocket in the beamand held against lateral movement therein, an extension on thecore-piece of each solenoid arranged to engage with one of the saidpianokeys to actuate the latter, a source of electric energy in circuitwith the solenoids, and contact making and breaking devices.

3. In an electrical self-playing musical instrument the combination withthe soundproducing devices, of a cross-beam located below said devices,said beam having a plurality of vertical openings extending therethrougharranged in longitudinal alinement, a solenoid in each of said openings,said solenoids being held against movement in said openings, a coremovable in each solenoid, a contact making and breaking device for eachsolenoid, and means carried by the core and extending in alinement withthe axis of the core for actuating the sound-producing devices duringthe movement of the core upwardly by the action of the solenoid, saidcore and means being free to move in the opposite direction independentof the sound-producing devices.

4. In an electrical self-playing musical instrument, the combinationwith the soundproducing devices, of a cross-beam provided with aplurality of pockets, a wire helix in each pocket, an iron core movablein each helix, a connector attached to the upper end of each core, a rodadjustably connected to each connector at one end and having itsopposite and arranged to actuate the soundproducing devices, a felt'disk or cushion below each connector, and contact making and breakingdevices in circuit with the helices.

5. In an electrical self playing musical instrument the combination withthe soundproducing devices, of a solenoid for each device, a weightedcore movable vertically within each solenoid,- the action of thesolenoid moving the core in opposition to the weight thereof, a contact,making and breaking device, and means carried by the core and extendingin alinement with the axis of the core for actuating the sound-producingdevices during the movement of the core upwardly by the action of thesolenoid, said core and means being free to move in the oppositedirection independent of the sound-producing devices under the action ofthe core and the actuating means carried thereby. I

6. In an electrical self-playing musical instrument, the combinationwith the sound producing devices; of a solenoid for each device, havingits core-piece extending in a vertical direction; means for normallyholding said core-piece suspended; an actuating-rod extending verticallyfrom and in alinement with the axis of said core-piece to impart amovementto the device in one direction; and an electric make-and-breakdevice for intermittently energizing said solenoid, whereby saidcore-piece will be positively moved to actuate the device by electricalaction, said rod and core-piece being free to move in the oppositedirection independent of the sound-producing devices.

7. The combination with sound-producing devices; of a solenoid for eachdevice, having its core extending vertically; a connector forming thesole support for the core when in inoperative position; connector andsupported thereby for actuating the devices; and energizing means forsaid solenoid, said means moving the core in opposition to the weightthereof.

8. The combination with sound-producing devices; of a solenoid for eachdevice, having its core extending vertically; a connector normallyresting on the helix of the solenoid and insulated therefrom, saidconnector by means normally located on the helix of the solenoid formingthe sole support for the core when in inoperative position; a rodcarried by said connector for actuating the devices; and energizingmeans for said solenoid, the return movement being independent of themovement of the sound-producing devices.

9. The combination with sound-producing devices; of a solenoid for eachdevice, hav-' ing its core extending vertically; a connector adjustablyconnected to said core and forming the sole support therefor when ininoperative position; a rod for actuatingsaid device, adj ustablysecured to said connector and supported thereby, whereby the length ofmovement of the core may be varied without varying the length ofmovement of the device; and energizing means for said solenoid, saidmeans moving the core in opposition to the Weight thereof.

10. The combination with the sound-producing devices; of a solenoid foreach device, each solenoid having its core adjustably suspended withinits helix, said core having adjustable means for moving its device inone direction, the adjustment of said core serving to regulate therapidity of movement of the core within its helix; a source ofelectrical energy in circuit with the helices; and a make-and-breakdevice for each helix.

In testimony whereof I afiix my signature in presence of two witnesses.

GEORGE HOWLETT DAVIS.

Witnesses:

EDWIN FRENCH, J r., JOHN T. SAoKs.

a rod carried by said

